diff --git a/lib/api/v3/activities/activities_api.rb b/lib/api/v3/activities/activities_api.rb
index 0e4d0a5271..7c35767059 100644
--- a/lib/api/v3/activities/activities_api.rb
+++ b/lib/api/v3/activities/activities_api.rb
@@ -17,6 +17,7 @@ module API
             end
 
             get do
+              authorize(:work_packages, :show, context: @activity.Journalable.project)
               @representer.to_json
             end